title: Multi-channel open tubular traps for headspace sampling, gas chromatographic fraction collection and olfactory assessment of milk volatiles.
abstract: A headspace sampling method is described for concentrating milk volatiles onto a multi-channel open tubular silicone rubber trap (MCT) for thermal desorption into a GC-FID. Sections of the chromatographic profile, single peaks or combinations of compounds are recaptured with secondary MCTs during a subsequent run. The recaptured aroma is released in a controlled manner by heating the MCT in a portable heating device. An aroma release window of several minutes allows up to six people the opportunity to sniff each aroma fraction more than once. Olfactory results suggest that a synergistic combination of 2-heptanone and 2-nonanone could be responsible for a pungent cheese, sour milk-like aroma. MCTs containing single components or fractions can be desorbed into a GC-MS for compound identification.
authors.affiliation: Department of Chemistry, University of Pretoria, Hatfield 0002, South Africa.
authors.forename: Yvette
authors.initials: Y
authors.lastname: Naudé
authors.forename: Marleen
authors.initials: M
authors.lastname: van Aardt
authors.forename: Egmont Richard
authors.initials: ER
authors.lastname: Rohwer
mesh_terms: D000818:Animals; D005591:Chemical Fractionation / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D007659:Ketones / Q000302:isolation & purification*; D008892:Milk / Q000737:chemistry*; D009812:Odorants / Q000032:analysis; D012903:Smell; D055549:Volatile Organic Compounds / Q000302:isolation & purification*
chemical_list: D007659:Ketones; D055549:Volatile Organic Compounds; C011917:2-heptanone; C026636:2-nonanone